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Chondrosarcoma is a primary malignant bone cancer, with a potent capacity to invade locally and cause distant metastasis, especially to the lungs. Patients diagnosed with chondrosarcoma have poor prognosis. Berberine, an active component of the Ranunculaceae and Papaveraceae families of plant, has been proven to induce tumor apoptosis and to prevent the metastasis of cancer cells. However, the effects of berberine in human chondrosarcoma are largely unknown. In this study, we found that berberine did not induce cell apoptosis in human primary chondrocytes and chondrosarcoma cells. However, at noncytotoxic concentrations, berberine reduced the migration and invasion of chondrosarcoma cancer cells. Integrins are the major adhesive molecules in mammalian cells and have been associated with the metastasis of cancer cells. We also found that incubation of chondrosarcoma cells with berberine reduced mRNA transcription for, and cell surface expression of, the αvβ3 integrin, with additional inhibitory effects on PKCδ, c-Src, and NF-kB activation. Thus, berberine may be a novel antimetastasis agent for the treatment of metastatic chondrosarcoma. [ABSTRACT FROM AUTHOR]

The aim of this study is to explore the mechanisms by which electroacupuncture (EA) enhances the hypoglycemic effect of exogenous insulin in a streptozotocin- (STZ-) diabetic rats. Animals in the EA group were anesthetized and subjected to the insulin challenge test (ICT) and EA for 60 minutes. In the control group, rats were subjected to the same treatment with the exception of EA stimulation. Blood samples were drawn to measure changes in plasma glucose, free fatty acids (FFA), and insulin levels. Western blot was used to assay proteins involved in insulin signaling. Furthermore, atropine, hemicholinium-3 (HC-3), and Eserine were used to explore the relationship between EA and cholinergic nerve activation during ICT. EA augmented the blood glucose-lowering effects of EA by activating the cholinergic nerves in STZ rats that had been exposed to exogenous insulin. This phenomenon may be related to enhancement of insulin signaling rather than to changes in FFA concentration. [ABSTRACT FROM AUTHOR]

Animal studies have shown that electroacupuncture (EA) at Zusanli (ST-36) and Zhongwan (CV-12) acupoints reduces plasma glucose concentrations in rats with type II diabetes. However, whether EA reduces plasma glucose levels in type I diabetes is still unknown. In this study, we explore the various non-insulin-dependent pathways involved in EA-induced lowering of plasma glucose. Streptozotocin (STZ) (60 mg kg-1, i.v.) was administered via the femoral vein to induce insulin-dependent diabetes in non-adrenalectomized and in adrenalectomomized rats. EA (15Hz) was applied for 30min to bilateral ST-36 acupoints after administration of Atropine (0.1 mg kg-1 i.p.), Eserine (0.01mg kg-1 i.p.), or Hemicholinium-3 (5 μg kg-1 i.p.) in nonadrenalectomized rats. Rats administered acetylcholine (0.01mg kg-1 i.v.) did not undergo EA. Adrenalectomized rats underwent EA at bilateral ST-36 acupoints without further treatment. Blood samples were drawn from all rats before and after EA to measure changes in plasma glucose levels. Expression of insulin signaling proteins (IRS1, AKT2) in atropine-exposed rats before and after EA was measured by western blot. Atropine and hemicholinium-3 completely blocked the plasma glucose lowering effects of EA, whereas eserine led to a significant hypoglycemic response. In addition, plasma glucose levels after administration of acetylcholine were significantly lower than the fasting glucose levels. In STZ-adrenalectomized rats, EA did not induce a hypoglycemic response. EA stimulated the expression of IRS1 and AKT2 and atropine treatment blocked the EA-induced expression of those insulin signaling proteins. Taken together, EA at the ST-36 acupoint reduces plasma glucose concentrations by stimulating the cholinergic nerves. [ABSTRACT FROM AUTHOR]